Blepharitis is best described as:

Blepharitis refers specifically to the inflammation of the edges of the eyelids. This condition can occur as a result of various factors such as bacteria, skin conditions, or allergies, and typically presents with symptoms like redness, irritation, and flaking skin near the eyelids. Understanding this definition is crucial for properly diagnosing and treating eye-related issues.

The other choices do not accurately describe blepharitis. For instance, double vision refers to a visual disturbance where a person sees two images of a single object, which is unrelated to eyelid inflammation. The turning outward of the eyelids is known as ectropion, while loss of visual accommodation refers to the inability of the eye to focus on near objects, often associated with aging. None of these conditions relate directly to the inflammation that characterizes blepharitis.